We should speak of it as an attack on history, which it was. This was the church founded by Denmark Vesey, who planned a slave revolt in 1822. Vesey was convicted in a secret trial in which many of the witnesses testified after being tortured. After they hung him, a mob burned down the church he built. His sons rebuilt it. On Wednesday night, someone turned it into a slaughter pen.
We should speak of it as an assault on the idea of a political commonwealth, which is what it was. And we should speak of it as one more example of all of these, another link in a bloody chain of events that reaches all the way back to African wharves and Southern docks. It is not an isolated incident, not if you consider history as something alive that can live and breathe and bleed.